Touch.java revision 38e98fccfab9592f871f3066f8569c559f1ee226
19066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project/* 29066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Copyright (C) 2008 The Android Open Source Project 39066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 49066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Licensed under the Apache License, Version 2.0 (the "License"); 59066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * you may not use this file except in compliance with the License. 69066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * You may obtain a copy of the License at 79066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 89066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * http://www.apache.org/licenses/LICENSE-2.0 99066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 109066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Unless required by applicable law or agreed to in writing, software 119066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * distributed under the License is distributed on an "AS IS" BASIS, 129066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 139066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * See the License for the specific language governing permissions and 149066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * limitations under the License. 159066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 169066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 179066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectpackage android.text.method; 189066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 199066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectimport android.text.Layout; 209066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectimport android.text.NoCopySpan; 219066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectimport android.text.Layout.Alignment; 229066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectimport android.text.Spannable; 239066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectimport android.view.MotionEvent; 249066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectimport android.view.ViewConfiguration; 259066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectimport android.widget.TextView; 269066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 279066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectpublic class Touch { 289066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project private Touch() { } 299066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 309066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project /** 319066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Scrolls the specified widget to the specified coordinates, except 329066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * constrains the X scrolling position to the horizontal regions of 339066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * the text that will be visible after scrolling to the specified 349066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Y position. 359066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 369066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public static void scrollTo(TextView widget, Layout layout, int x, int y) { 379066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project int padding = widget.getTotalPaddingTop() + 389066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project widget.getTotalPaddingBottom(); 399066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project int top = layout.getLineForVertical(y); 409066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project int bottom = layout.getLineForVertical(y + widget.getHeight() - 419066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project padding); 429066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 439066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project int left = Integer.MAX_VALUE; 449066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project int right = 0; 459066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project Alignment a = null; 469066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 479066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project for (int i = top; i <= bottom; i++) { 489066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project left = (int) Math.min(left, layout.getLineLeft(i)); 499066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project right = (int) Math.max(right, layout.getLineRight(i)); 509066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 519066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project if (a == null) { 529066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project a = layout.getParagraphAlignment(i); 539066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 549066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 559066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 569066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project padding = widget.getTotalPaddingLeft() + widget.getTotalPaddingRight(); 579066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project int width = widget.getWidth(); 589066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project int diff = 0; 599066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 609066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project if (right - left < width - padding) { 619066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project if (a == Alignment.ALIGN_CENTER) { 629066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project diff = (width - padding - (right - left)) / 2; 639066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } else if (a == Alignment.ALIGN_OPPOSITE) { 649066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project diff = width - padding - (right - left); 659066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 669066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 679066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 689066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project x = Math.min(x, right - (width - padding) - diff); 699066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project x = Math.max(x, left - diff); 709066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 719066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project widget.scrollTo(x, y); 729066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 739066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 749066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project /** 759066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Handles touch events for dragging. You may want to do other actions 769066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * like moving the cursor on touch as well. 779066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 789066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public static boolean onTouchEvent(TextView widget, Spannable buffer, 799066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project MotionEvent event) { 809066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project DragState[] ds; 819066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 829066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project switch (event.getAction()) { 839066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project case MotionEvent.ACTION_DOWN: 8438e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn buffer.setSpan(new DragState(event.getX(), event.getY(), 8538e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn widget.getScrollX(), widget.getScrollY()), 8638e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn 0, 0, Spannable.SPAN_MARK_MARK); 879066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return true; 889066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 899066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project case MotionEvent.ACTION_UP: 909066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project ds = buffer.getSpans(0, buffer.length(), DragState.class); 919066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 929066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project for (int i = 0; i < ds.length; i++) { 939066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project buffer.removeSpan(ds[i]); 949066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 959066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 969066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project if (ds.length > 0 && ds[0].mUsed) { 979066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return true; 989066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } else { 999066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return false; 1009066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 1019066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 1029066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project case MotionEvent.ACTION_MOVE: 1039066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project ds = buffer.getSpans(0, buffer.length(), DragState.class); 1049066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 1059066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project if (ds.length > 0) { 1069066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project if (ds[0].mFarEnough == false) { 1079066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project int slop = ViewConfiguration.get(widget.getContext()).getScaledTouchSlop(); 1089066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 1099066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project if (Math.abs(event.getX() - ds[0].mX) >= slop || 1109066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project Math.abs(event.getY() - ds[0].mY) >= slop) { 1119066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project ds[0].mFarEnough = true; 1129066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 1139066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 1149066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 1159066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project if (ds[0].mFarEnough) { 1169066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project ds[0].mUsed = true; 1179066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 1189066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project float dx = ds[0].mX - event.getX(); 1199066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project float dy = ds[0].mY - event.getY(); 1209066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 1219066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project ds[0].mX = event.getX(); 1229066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project ds[0].mY = event.getY(); 1239066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 1249066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project int nx = widget.getScrollX() + (int) dx; 1259066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project int ny = widget.getScrollY() + (int) dy; 1269066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 1279066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project int padding = widget.getTotalPaddingTop() + 1289066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project widget.getTotalPaddingBottom(); 1299066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project Layout layout = widget.getLayout(); 1309066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 1319066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project ny = Math.min(ny, layout.getHeight() - (widget.getHeight() - 1329066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project padding)); 1339066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project ny = Math.max(ny, 0); 1349066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 1359066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project scrollTo(widget, layout, nx, ny); 1369066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project widget.cancelLongPress(); 1379066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return true; 1389066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 1399066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 1409066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 1419066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 1429066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return false; 1439066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 1449066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 14538e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn public static int getInitialScrollX(TextView widget, Spannable buffer) { 14638e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn DragState[] ds = buffer.getSpans(0, buffer.length(), DragState.class); 14738e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn return ds.length > 0 ? ds[0].mScrollX : -1; 14838e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn } 14938e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn 15038e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn public static int getInitialScrollY(TextView widget, Spannable buffer) { 15138e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn DragState[] ds = buffer.getSpans(0, buffer.length(), DragState.class); 15238e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn return ds.length > 0 ? ds[0].mScrollY : -1; 15338e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn } 15438e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn 1559066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project private static class DragState implements NoCopySpan { 1569066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public float mX; 1579066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public float mY; 15838e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn public int mScrollX; 15938e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn public int mScrollY; 1609066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public boolean mFarEnough; 1619066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public boolean mUsed; 1629066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 16338e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn public DragState(float x, float y, int scrollX, int scrollY) { 1649066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project mX = x; 1659066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project mY = y; 16638e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn mScrollX = scrollX; 16738e98fccfab9592f871f3066f8569c559f1ee226Dianne Hackborn mScrollY = scrollY; 1689066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 1699066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 1709066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project} 171