ImageButton.java revision 4e8620f868e2490782ebb960404140ea9482c91d
19066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project/* 29066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Copyright (C) 2007 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.widget; 189066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 199066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectimport android.content.Context; 209066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectimport android.os.Handler; 219066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectimport android.os.Message; 229066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectimport android.util.AttributeSet; 239066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectimport android.view.MotionEvent; 249066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectimport android.widget.RemoteViews.RemoteView; 259066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 269066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectimport java.util.Map; 279066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 289066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project/** 299066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * <p> 3084971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * Displays a button with an image (instead of text) that can be pressed 3184971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * or clicked by the user. By default, an ImageButton looks like a regular 3284971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * {@link android.widget.Button}, with the standard button background 3384971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * that changes color during different button states. The image on the surface 3484971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * of the button is defined either by the {@code android:src} attribute in the 354e8620f868e2490782ebb960404140ea9482c91dBen Dodson * {@code <ImageButton>} XML element or by the 3684971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * {@link #setImageResource(int)} method.</p> 3784971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * 3884971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * <p>To remove the standard button background image, define your own 3984971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * background image or set the background color to be transparent.</p> 4084971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * <p>To indicate the different button states (focused, selected, etc.), you can 4184971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * define a different image for each state. E.g., a blue image by default, an 4284971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * orange one for when focused, and a yellow one for when pressed. An easy way to 4384971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * do this is with an XML drawable "selector." For example:</p> 4484971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * <pre> 4584971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * <?xml version="1.0" encoding="utf-8"?> 4684971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * <selector xmlns:android="http://schemas.android.com/apk/res/android"> 4784971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * <item android:state_pressed="true" 4884971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * android:drawable="@drawable/button_pressed" /> <!-- pressed --> 4984971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * <item android:state_focused="true" 5084971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * android:drawable="@drawable/button_focused" /> <!-- focused --> 51aa3b5961c0142fe2fe87a5e4f67a12b3728f1beaScott Main * <item android:drawable="@drawable/button_normal" /> <!-- default --> 5284971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * </selector></pre> 5384971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * 5484971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * <p>Save the XML file in your project {@code res/drawable/} folder and then 5584971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * reference it as a drawable for the source of your ImageButton (in the 5684971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * {@code android:src} attribute). Android will automatically change the image 5784971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * based on the state of the button and the corresponding images 5884971ae0109bdfae79f3c9d15edf400fa5129f3dScott Main * defined in the XML.</p> 599066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 604e8620f868e2490782ebb960404140ea9482c91dBen Dodson * <p>The order of the {@code <item>} elements is important because they are 61aa3b5961c0142fe2fe87a5e4f67a12b3728f1beaScott Main * evaluated in order. This is why the "normal" button image comes last, because 62aa3b5961c0142fe2fe87a5e4f67a12b3728f1beaScott Main * it will only be applied after {@code android:state_pressed} and {@code 63aa3b5961c0142fe2fe87a5e4f67a12b3728f1beaScott Main * android:state_focused} have both evaluated false.</p> 64aa3b5961c0142fe2fe87a5e4f67a12b3728f1beaScott Main * 6541ec65355bd6ded652769725b276d47c54a0d913Scott Main * <p>See the <a href="{@docRoot}resources/tutorials/views/hello-formstuff.html">Form Stuff 6641ec65355bd6ded652769725b276d47c54a0d913Scott Main * tutorial</a>.</p> 6741ec65355bd6ded652769725b276d47c54a0d913Scott Main * 689066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * <p><strong>XML attributes</strong></p> 699066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * <p> 709066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * See {@link android.R.styleable#ImageView Button Attributes}, 719066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * {@link android.R.styleable#View View Attributes} 729066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * </p> 739066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 749066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project@RemoteView 759066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectpublic class ImageButton extends ImageView { 769066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public ImageButton(Context context) { 779066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project this(context, null); 789066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 799066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 809066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public ImageButton(Context context, AttributeSet attrs) { 819066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project this(context, attrs, com.android.internal.R.attr.imageButtonStyle); 829066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 839066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 849066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public ImageButton(Context context, AttributeSet attrs, int defStyle) { 859066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project super(context, attrs, defStyle); 869066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project setFocusable(true); 879066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 889066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 899066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project @Override 909066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project protected boolean onSetAlpha(int alpha) { 919066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return false; 929066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 939066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project} 94