CheckedTextView.java revision 75986cf9bc57ef11ad70f36fb77fbbf5d63af6ec 
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.accessibility.AccessibilityEvent;
28
29
30/**
31 * An extension to TextView that supports the {@link android.widget.Checkable} interface.
32 * This is useful when used in a {@link android.widget.ListView ListView} where the it's
33 * {@link android.widget.ListView#setChoiceMode(int) setChoiceMode} has been set to
34 * something other than {@link android.widget.ListView#CHOICE_MODE_NONE CHOICE_MODE_NONE}.
35 *
36 */
37public class CheckedTextView extends TextView implements Checkable {
38    private boolean mChecked;
39    private int mCheckMarkResource;
40    private Drawable mCheckMarkDrawable;
41    private int mBasePaddingRight;
42    private int mCheckMarkWidth;
43
44    private static final int[] CHECKED_STATE_SET = {
45        R.attr.state_checked
46    };
47
48    public CheckedTextView(Context context) {
49        this(context, null);
50    }
51
52    public CheckedTextView(Context context, AttributeSet attrs) {
53        this(context, attrs, 0);
54    }
55
56    public CheckedTextView(Context context, AttributeSet attrs, int defStyle) {
57        super(context, attrs, defStyle);
58
59        TypedArray a = context.obtainStyledAttributes(attrs,
60                R.styleable.CheckedTextView, defStyle, 0);
61
62        Drawable d = a.getDrawable(R.styleable.CheckedTextView_checkMark);
63        if (d != null) {
64            setCheckMarkDrawable(d);
65        }
66
67        boolean checked = a.getBoolean(R.styleable.CheckedTextView_checked, false);
68        setChecked(checked);
69
70        a.recycle();
71    }
72
73    public void toggle() {
74        setChecked(!mChecked);
75    }
76
77    public boolean isChecked() {
78        return mChecked;
79    }
80
81    /**
82     * <p>Changes the checked state of this text view.</p>
83     *
84     * @param checked true to check the text, false to uncheck it
85     */
86    public void setChecked(boolean checked) {
87        if (mChecked != checked) {
88            mChecked = checked;
89            refreshDrawableState();
90        }
91    }
92
93
94    /**
95     * Set the checkmark to a given Drawable, identified by its resourece id. This will be drawn
96     * when {@link #isChecked()} is true.
97     *
98     * @param resid The Drawable to use for the checkmark.
99     */
100    public void setCheckMarkDrawable(int resid) {
101        if (resid != 0 && resid == mCheckMarkResource) {
102            return;
103        }
104
105        mCheckMarkResource = resid;
106
107        Drawable d = null;
108        if (mCheckMarkResource != 0) {
109            d = getResources().getDrawable(mCheckMarkResource);
110        }
111        setCheckMarkDrawable(d);
112    }
113
114    /**
115     * Set the checkmark to a given Drawable. This will be drawn when {@link #isChecked()} is true.
116     *
117     * @param d The Drawable to use for the checkmark.
118     */
119    public void setCheckMarkDrawable(Drawable d) {
120        if (d != null) {
121            if (mCheckMarkDrawable != null) {
122                mCheckMarkDrawable.setCallback(null);
123                unscheduleDrawable(mCheckMarkDrawable);
124            }
125            d.setCallback(this);
126            d.setVisible(getVisibility() == VISIBLE, false);
127            d.setState(CHECKED_STATE_SET);
128            setMinHeight(d.getIntrinsicHeight());
129
130            mCheckMarkWidth = d.getIntrinsicWidth();
131            mPaddingRight = mCheckMarkWidth + mBasePaddingRight;
132            d.setState(getDrawableState());
133            mCheckMarkDrawable = d;
134        } else {
135            mPaddingRight = mBasePaddingRight;
136        }
137        requestLayout();
138    }
139
140    @Override
141    public void setPadding(int left, int top, int right, int bottom) {
142        super.setPadding(left, top, right, bottom);
143        mBasePaddingRight = mPaddingRight;
144    }
145
146    @Override
147    protected void onDraw(Canvas canvas) {
148        super.onDraw(canvas);
149
150        final Drawable checkMarkDrawable = mCheckMarkDrawable;
151        if (checkMarkDrawable != null) {
152            final int verticalGravity = getGravity() & Gravity.VERTICAL_GRAVITY_MASK;
153            final int height = checkMarkDrawable.getIntrinsicHeight();
154
155            int y = 0;
156
157            switch (verticalGravity) {
158                case Gravity.BOTTOM:
159                    y = getHeight() - height;
160                    break;
161                case Gravity.CENTER_VERTICAL:
162                    y = (getHeight() - height) / 2;
163                    break;
164            }
165
166            int right = getWidth();
167            checkMarkDrawable.setBounds(
168                    right - mCheckMarkWidth - mBasePaddingRight,
169                    y,
170                    right - mBasePaddingRight,
171                    y + height);
172            checkMarkDrawable.draw(canvas);
173        }
174    }
175
176    @Override
177    protected int[] onCreateDrawableState(int extraSpace) {
178        final int[] drawableState = super.onCreateDrawableState(extraSpace + 1);
179        if (isChecked()) {
180            mergeDrawableStates(drawableState, CHECKED_STATE_SET);
181        }
182        return drawableState;
183    }
184
185    @Override
186    protected void drawableStateChanged() {
187        super.drawableStateChanged();
188
189        if (mCheckMarkDrawable != null) {
190            int[] myDrawableState = getDrawableState();
191
192            // Set the state of the Drawable
193            mCheckMarkDrawable.setState(myDrawableState);
194
195            invalidate();
196        }
197    }
198
199    @Override
200    public boolean dispatchPopulateAccessibilityEvent(AccessibilityEvent event) {
201        boolean populated = super.dispatchPopulateAccessibilityEvent(event);
202        if (!populated) {
203            event.setChecked(mChecked);
204        }
205        return populated;
206    }
207}
208