CheckedTextView.java revision 77e9a28e2faa36f127231b842476d47f9823a83a 
1/*
2 * Copyright (C) 2007 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package android.widget;
18
19import com.android.internal.R;
20
21import android.content.Context;
22import android.content.res.TypedArray;
23import android.graphics.Canvas;
24import android.graphics.drawable.Drawable;
25import android.util.AttributeSet;
26import android.view.Gravity;
27import android.view.ViewDebug;
28import android.view.accessibility.AccessibilityEvent;
29import android.view.accessibility.AccessibilityNodeInfo;
30
31
32/**
33 * An extension to TextView that supports the {@link android.widget.Checkable} interface.
34 * This is useful when used in a {@link android.widget.ListView ListView} where the it's
35 * {@link android.widget.ListView#setChoiceMode(int) setChoiceMode} has been set to
36 * something other than {@link android.widget.ListView#CHOICE_MODE_NONE CHOICE_MODE_NONE}.
37 *
38 * @attr ref android.R.styleable#CheckedTextView_checked
39 * @attr ref android.R.styleable#CheckedTextView_checkMark
40 */
41public class CheckedTextView extends TextView implements Checkable {
42    private boolean mChecked;
43    private int mCheckMarkResource;
44    private Drawable mCheckMarkDrawable;
45    private int mBasePadding;
46    private int mCheckMarkWidth;
47    private boolean mNeedRequestlayout;
48
49    private static final int[] CHECKED_STATE_SET = {
50        R.attr.state_checked
51    };
52
53    public CheckedTextView(Context context) {
54        this(context, null);
55    }
56
57    public CheckedTextView(Context context, AttributeSet attrs) {
58        this(context, attrs, R.attr.checkedTextViewStyle);
59    }
60
61    public CheckedTextView(Context context, AttributeSet attrs, int defStyle) {
62        super(context, attrs, defStyle);
63
64        TypedArray a = context.obtainStyledAttributes(attrs,
65                R.styleable.CheckedTextView, defStyle, 0);
66
67        Drawable d = a.getDrawable(R.styleable.CheckedTextView_checkMark);
68        if (d != null) {
69            setCheckMarkDrawable(d);
70        }
71
72        boolean checked = a.getBoolean(R.styleable.CheckedTextView_checked, false);
73        setChecked(checked);
74
75        a.recycle();
76    }
77
78    public void toggle() {
79        setChecked(!mChecked);
80    }
81
82    @ViewDebug.ExportedProperty
83    public boolean isChecked() {
84        return mChecked;
85    }
86
87    /**
88     * <p>Changes the checked state of this text view.</p>
89     *
90     * @param checked true to check the text, false to uncheck it
91     */
92    public void setChecked(boolean checked) {
93        if (mChecked != checked) {
94            mChecked = checked;
95            refreshDrawableState();
96            notifyViewAccessibilityStateChangedIfNeeded(
97                    AccessibilityEvent.CONTENT_CHANGE_TYPE_UNDEFINED);
98        }
99    }
100
101
102    /**
103     * Set the checkmark to a given Drawable, identified by its resourece id. This will be drawn
104     * when {@link #isChecked()} is true.
105     *
106     * @param resid The Drawable to use for the checkmark.
107     *
108     * @see #setCheckMarkDrawable(Drawable)
109     * @see #getCheckMarkDrawable()
110     *
111     * @attr ref android.R.styleable#CheckedTextView_checkMark
112     */
113    public void setCheckMarkDrawable(int resid) {
114        if (resid != 0 && resid == mCheckMarkResource) {
115            return;
116        }
117
118        mCheckMarkResource = resid;
119
120        Drawable d = null;
121        if (mCheckMarkResource != 0) {
122            d = getResources().getDrawable(mCheckMarkResource);
123        }
124        setCheckMarkDrawable(d);
125    }
126
127    /**
128     * Set the checkmark to a given Drawable. This will be drawn when {@link #isChecked()} is true.
129     *
130     * @param d The Drawable to use for the checkmark.
131     *
132     * @see #setCheckMarkDrawable(int)
133     * @see #getCheckMarkDrawable()
134     *
135     * @attr ref android.R.styleable#CheckedTextView_checkMark
136     */
137    public void setCheckMarkDrawable(Drawable d) {
138        if (mCheckMarkDrawable != null) {
139            mCheckMarkDrawable.setCallback(null);
140            unscheduleDrawable(mCheckMarkDrawable);
141        }
142        mNeedRequestlayout = (d != mCheckMarkDrawable);
143        if (d != null) {
144            d.setCallback(this);
145            d.setVisible(getVisibility() == VISIBLE, false);
146            d.setState(CHECKED_STATE_SET);
147            setMinHeight(d.getIntrinsicHeight());
148
149            mCheckMarkWidth = d.getIntrinsicWidth();
150            d.setState(getDrawableState());
151        } else {
152            mCheckMarkWidth = 0;
153        }
154        mCheckMarkDrawable = d;
155        // Do padding resolution. This will call internalSetPadding() and do a requestLayout() if needed.
156        resolvePadding();
157    }
158
159    /**
160     * Gets the checkmark drawable
161     *
162     * @return The drawable use to represent the checkmark, if any.
163     *
164     * @see #setCheckMarkDrawable(Drawable)
165     * @see #setCheckMarkDrawable(int)
166     *
167     * @attr ref android.R.styleable#CheckedTextView_checkMark
168     */
169    public Drawable getCheckMarkDrawable() {
170        return mCheckMarkDrawable;
171    }
172
173    /**
174     * @hide
175     */
176    @Override
177    protected void internalSetPadding(int left, int top, int right, int bottom) {
178        super.internalSetPadding(left, top, right, bottom);
179        setBasePadding(isLayoutRtl());
180    }
181
182    @Override
183    public void onRtlPropertiesChanged(int layoutDirection) {
184        super.onRtlPropertiesChanged(layoutDirection);
185        updatePadding();
186    }
187
188    private void updatePadding() {
189        resetPaddingToInitialValues();
190        int newPadding = (mCheckMarkDrawable != null) ?
191                mCheckMarkWidth + mBasePadding : mBasePadding;
192        if (isLayoutRtl()) {
193            mNeedRequestlayout |= (mPaddingLeft != newPadding);
194            mPaddingLeft = newPadding;
195        } else {
196            mNeedRequestlayout |= (mPaddingRight != newPadding);
197            mPaddingRight = newPadding;
198        }
199        if (mNeedRequestlayout) {
200            requestLayout();
201            mNeedRequestlayout = false;
202        }
203    }
204
205    private void setBasePadding(boolean isLayoutRtl) {
206        if (isLayoutRtl) {
207            mBasePadding = mPaddingLeft;
208        } else {
209            mBasePadding = mPaddingRight;
210        }
211    }
212
213    @Override
214    protected void onDraw(Canvas canvas) {
215        super.onDraw(canvas);
216
217        final Drawable checkMarkDrawable = mCheckMarkDrawable;
218        if (checkMarkDrawable != null) {
219            final int verticalGravity = getGravity() & Gravity.VERTICAL_GRAVITY_MASK;
220            final int height = checkMarkDrawable.getIntrinsicHeight();
221
222            int y = 0;
223
224            switch (verticalGravity) {
225                case Gravity.BOTTOM:
226                    y = getHeight() - height;
227                    break;
228                case Gravity.CENTER_VERTICAL:
229                    y = (getHeight() - height) / 2;
230                    break;
231            }
232
233            final boolean isLayoutRtl = isLayoutRtl();
234            final int width = getWidth();
235            final int top = y;
236            final int bottom = top + height;
237            final int left;
238            final int right;
239            if (isLayoutRtl) {
240                left = mBasePadding;
241                right = left + mCheckMarkWidth;
242            } else {
243                right = width - mBasePadding;
244                left = right - mCheckMarkWidth;
245            }
246            checkMarkDrawable.setBounds(mScrollX + left, top, mScrollX + right, bottom);
247            checkMarkDrawable.draw(canvas);
248        }
249    }
250
251    @Override
252    protected int[] onCreateDrawableState(int extraSpace) {
253        final int[] drawableState = super.onCreateDrawableState(extraSpace + 1);
254        if (isChecked()) {
255            mergeDrawableStates(drawableState, CHECKED_STATE_SET);
256        }
257        return drawableState;
258    }
259
260    @Override
261    protected void drawableStateChanged() {
262        super.drawableStateChanged();
263
264        if (mCheckMarkDrawable != null) {
265            int[] myDrawableState = getDrawableState();
266
267            // Set the state of the Drawable
268            mCheckMarkDrawable.setState(myDrawableState);
269
270            invalidate();
271        }
272    }
273
274    @Override
275    public void onInitializeAccessibilityEvent(AccessibilityEvent event) {
276        super.onInitializeAccessibilityEvent(event);
277        event.setClassName(CheckedTextView.class.getName());
278        event.setChecked(mChecked);
279    }
280
281    @Override
282    public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
283        super.onInitializeAccessibilityNodeInfo(info);
284        info.setClassName(CheckedTextView.class.getName());
285        info.setCheckable(true);
286        info.setChecked(mChecked);
287    }
288}
289