CheckedTextView.java revision 977c9a5d3cb9ecd9190c37da25d1e7476a1dd0bb 
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 */
39public class CheckedTextView extends TextView implements Checkable {
40    private boolean mChecked;
41    private int mCheckMarkResource;
42    private Drawable mCheckMarkDrawable;
43    private int mBasePadding;
44    private int mCheckMarkWidth;
45    private boolean mNeedRequestlayout;
46
47    private static final int[] CHECKED_STATE_SET = {
48        R.attr.state_checked
49    };
50
51    public CheckedTextView(Context context) {
52        this(context, null);
53    }
54
55    public CheckedTextView(Context context, AttributeSet attrs) {
56        this(context, attrs, 0);
57    }
58
59    public CheckedTextView(Context context, AttributeSet attrs, int defStyle) {
60        super(context, attrs, defStyle);
61
62        TypedArray a = context.obtainStyledAttributes(attrs,
63                R.styleable.CheckedTextView, defStyle, 0);
64
65        Drawable d = a.getDrawable(R.styleable.CheckedTextView_checkMark);
66        if (d != null) {
67            setCheckMarkDrawable(d);
68        }
69
70        boolean checked = a.getBoolean(R.styleable.CheckedTextView_checked, false);
71        setChecked(checked);
72
73        a.recycle();
74    }
75
76    public void toggle() {
77        setChecked(!mChecked);
78    }
79
80    @ViewDebug.ExportedProperty
81    public boolean isChecked() {
82        return mChecked;
83    }
84
85    /**
86     * <p>Changes the checked state of this text view.</p>
87     *
88     * @param checked true to check the text, false to uncheck it
89     */
90    public void setChecked(boolean checked) {
91        if (mChecked != checked) {
92            mChecked = checked;
93            refreshDrawableState();
94        }
95    }
96
97
98    /**
99     * Set the checkmark to a given Drawable, identified by its resourece id. This will be drawn
100     * when {@link #isChecked()} is true.
101     *
102     * @param resid The Drawable to use for the checkmark.
103     */
104    public void setCheckMarkDrawable(int resid) {
105        if (resid != 0 && resid == mCheckMarkResource) {
106            return;
107        }
108
109        mCheckMarkResource = resid;
110
111        Drawable d = null;
112        if (mCheckMarkResource != 0) {
113            d = getResources().getDrawable(mCheckMarkResource);
114        }
115        setCheckMarkDrawable(d);
116    }
117
118    /**
119     * Set the checkmark to a given Drawable. This will be drawn when {@link #isChecked()} is true.
120     *
121     * @param d The Drawable to use for the checkmark.
122     */
123    public void setCheckMarkDrawable(Drawable d) {
124        if (mCheckMarkDrawable != null) {
125            mCheckMarkDrawable.setCallback(null);
126            unscheduleDrawable(mCheckMarkDrawable);
127        }
128        mNeedRequestlayout = (d != mCheckMarkDrawable);
129        if (d != null) {
130            d.setCallback(this);
131            d.setVisible(getVisibility() == VISIBLE, false);
132            d.setState(CHECKED_STATE_SET);
133            setMinHeight(d.getIntrinsicHeight());
134
135            mCheckMarkWidth = d.getIntrinsicWidth();
136            d.setState(getDrawableState());
137        } else {
138            mCheckMarkWidth = 0;
139        }
140        mCheckMarkDrawable = d;
141        // Do padding resolution. This will call setPadding() and do a requestLayout() if needed.
142        resolvePadding();
143    }
144
145    @Override
146    public void onPaddingChanged(int layoutDirection) {
147        int newPadding = (mCheckMarkDrawable != null) ?
148                mCheckMarkWidth + mBasePadding : mBasePadding;
149        mNeedRequestlayout |= (mPaddingRight != newPadding);
150        mPaddingRight = newPadding;
151        if (mNeedRequestlayout) {
152            requestLayout();
153            mNeedRequestlayout = false;
154        }
155    }
156
157    @Override
158    public void setPadding(int left, int top, int right, int bottom) {
159        super.setPadding(left, top, right, bottom);
160        mBasePadding = mPaddingRight;
161    }
162
163    @Override
164    public void setPaddingRelative(int start, int top, int end, int bottom) {
165        super.setPaddingRelative(start, top, end, bottom);
166        mBasePadding = getPaddingEnd();
167    }
168
169    @Override
170    protected void onDraw(Canvas canvas) {
171        super.onDraw(canvas);
172
173        final Drawable checkMarkDrawable = mCheckMarkDrawable;
174        if (checkMarkDrawable != null) {
175            final int verticalGravity = getGravity() & Gravity.VERTICAL_GRAVITY_MASK;
176            final int height = checkMarkDrawable.getIntrinsicHeight();
177
178            int y = 0;
179
180            switch (verticalGravity) {
181                case Gravity.BOTTOM:
182                    y = getHeight() - height;
183                    break;
184                case Gravity.CENTER_VERTICAL:
185                    y = (getHeight() - height) / 2;
186                    break;
187            }
188
189            int right = getWidth();
190            checkMarkDrawable.setBounds(
191                    right - mPaddingRight,
192                    y,
193                    right - mPaddingRight + mCheckMarkWidth,
194                    y + height);
195            checkMarkDrawable.draw(canvas);
196        }
197    }
198
199    @Override
200    protected int[] onCreateDrawableState(int extraSpace) {
201        final int[] drawableState = super.onCreateDrawableState(extraSpace + 1);
202        if (isChecked()) {
203            mergeDrawableStates(drawableState, CHECKED_STATE_SET);
204        }
205        return drawableState;
206    }
207
208    @Override
209    protected void drawableStateChanged() {
210        super.drawableStateChanged();
211
212        if (mCheckMarkDrawable != null) {
213            int[] myDrawableState = getDrawableState();
214
215            // Set the state of the Drawable
216            mCheckMarkDrawable.setState(myDrawableState);
217
218            invalidate();
219        }
220    }
221
222    @Override
223    public void onInitializeAccessibilityEvent(AccessibilityEvent event) {
224        super.onInitializeAccessibilityEvent(event);
225        event.setClassName(CheckedTextView.class.getName());
226        event.setChecked(mChecked);
227    }
228
229    @Override
230    public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
231        super.onInitializeAccessibilityNodeInfo(info);
232        info.setClassName(CheckedTextView.class.getName());
233        info.setChecked(mChecked);
234    }
235}
236