列表視圖中的單選按鈕

Question

我在列表視圖formate中顯示sting列表，我使用了默認列表視圖並使用simple_list_item_single_choice放置了一個單選按鈕。但是這顯示右側的單選按鈕，我想在左側顯示單選按鈕。是任何可能的使用默認列表視圖顯示左側的單選按鈕

Answer 1

simple_list_item_single_choice.xml使用CheckedTextView類

這裏是simple_list_item_single_choice.xml

<CheckedTextView xmlns:android="http://schemas.android.com/apk/res/android" 
    android:id="@android:id/text1" 
    android:layout_width="match_parent" 
    android:layout_height="?android:attr/listPreferredItemHeight" 
    android:textAppearance="?android:attr/textAppearanceLarge" 
    android:gravity="center_vertical" 
    android:checkMark="?android:attr/listChoiceIndicatorSingle" 
    android:paddingLeft="6dip" 
    android:paddingRight="6dip" 
    /> 

您需要爲您的需要自定義XML和使用CheckBox來實現你的目標 這裏是你的custom.xml

<CheckBox 
    xmlns:android="http://schemas.android.com/apk/res/android" 
    android:id="@android:id/text1" 
    android:layout_width="fill_parent" 
    android:layout_height="?android:attr/listPreferredItemHeight" 
    android:textAppearance="?android:attr/textAppearanceLarge" 
    android:gravity="center_vertical" 
    android:button="?android:attr/listChoiceIndicatorSingle" 
    android:paddingLeft="6dip" 
    android:paddingRight="6dip" 
    /> 

只需在代碼中使用custom.xml代替simple_list_item_single_choice.xml即可。

希望它可以幫助你。

Answer 2

這是不可能的，默認情況下單選按鈕在右側。如果你想要它在左邊，那麼你應該從SDK中獲取simple_list_item_single_choice.xml佈局的源代碼並進行適當的更改，然後使用此自定義佈局而不是默認佈局。

Answer 3

simple_list_item_single_choice使用CheckedTextView類。

<?xml version="1.0" encoding="utf-8"?> 
<!-- Copyright (C) 2008 The Android Open Source Project 

    Licensed under the Apache License, Version 2.0 (the "License"); 
    you may not use this file except in compliance with the License. 
    You may obtain a copy of the License at 

      http://www.apache.org/licenses/LICENSE-2.0 

    Unless required by applicable law or agreed to in writing, software 
    distributed under the License is distributed on an "AS IS" BASIS, 
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
    See the License for the specific language governing permissions and 
    limitations under the License. 
--> 

<CheckedTextView xmlns:android="http://schemas.android.com/apk/res/android" 
    android:id="@android:id/text1" 
    android:layout_width="match_parent" 
    android:layout_height="?android:attr/listPreferredItemHeight" 
    android:textAppearance="?android:attr/textAppearanceLarge" 
    android:gravity="center_vertical" 
    android:checkMark="?android:attr/listChoiceIndicatorSingle" 
    android:paddingLeft="6dip" 
    android:paddingRight="6dip" 
/> 

CheckedTextView類是android.widget包。

下面這個類的來源。

/*

* Copyright (C) 2007 The Android Open Source Project 
* 
* Licensed under the Apache License, Version 2.0 (the "License"); 
* you may not use this file except in compliance with the License. 
* You may obtain a copy of the License at 
* 
*  http://www.apache.org/licenses/LICENSE-2.0 
* 
* Unless required by applicable law or agreed to in writing, software 
* distributed under the License is distributed on an "AS IS" BASIS, 
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
* See the License for the specific language governing permissions and 
* limitations under the License. 
*/ 

package android.widget; 

import com.android.internal.R; 

import android.content.Context; 
import android.content.res.TypedArray; 
import android.graphics.Canvas; 
import android.graphics.drawable.Drawable; 
import android.util.AttributeSet; 
import android.view.Gravity; 
import android.view.ViewDebug; 
import android.view.accessibility.AccessibilityEvent; 


/** 
* An extension to TextView that supports the {@link android.widget.Checkable} interface. 
* This is useful when used in a {@link android.widget.ListView ListView} where the it's 
* {@link android.widget.ListView#setChoiceMode(int) setChoiceMode} has been set to 
* something other than {@link android.widget.ListView#CHOICE_MODE_NONE CHOICE_MODE_NONE}. 
* 
*/ 
public class CheckedTextView extends TextView implements Checkable { 
    private boolean mChecked; 
    private int mCheckMarkResource; 
    private Drawable mCheckMarkDrawable; 
    private int mBasePaddingRight; 
    private int mCheckMarkWidth; 

    private static final int[] CHECKED_STATE_SET = { 
     R.attr.state_checked 
    }; 

    public CheckedTextView(Context context) { 
     this(context, null); 
    } 

    public CheckedTextView(Context context, AttributeSet attrs) { 
     this(context, attrs, 0); 
    } 

    public CheckedTextView(Context context, AttributeSet attrs, int defStyle) { 
     super(context, attrs, defStyle); 

     TypedArray a = context.obtainStyledAttributes(attrs, 
       R.styleable.CheckedTextView, defStyle, 0); 

     Drawable d = a.getDrawable(R.styleable.CheckedTextView_checkMark); 
     if (d != null) { 
      setCheckMarkDrawable(d); 
     } 

     boolean checked = a.getBoolean(R.styleable.CheckedTextView_checked, false); 
     setChecked(checked); 

     a.recycle(); 
    } 

    public void toggle() { 
     setChecked(!mChecked); 
    } 

    @ViewDebug.ExportedProperty 
    public boolean isChecked() { 
     return mChecked; 
    } 

    /** 
    * <p>Changes the checked state of this text view.</p> 
    * 
    * @param checked true to check the text, false to uncheck it 
    */ 
    public void setChecked(boolean checked) { 
     if (mChecked != checked) { 
      mChecked = checked; 
      refreshDrawableState(); 
     } 
    } 


    /** 
    * Set the checkmark to a given Drawable, identified by its resourece id. This will be drawn 
    * when {@link #isChecked()} is true. 
    * 
    * @param resid The Drawable to use for the checkmark. 
    */ 
    public void setCheckMarkDrawable(int resid) { 
     if (resid != 0 && resid == mCheckMarkResource) { 
      return; 
     } 

     mCheckMarkResource = resid; 

     Drawable d = null; 
     if (mCheckMarkResource != 0) { 
      d = getResources().getDrawable(mCheckMarkResource); 
     } 
     setCheckMarkDrawable(d); 
    } 

    /** 
    * Set the checkmark to a given Drawable. This will be drawn when {@link #isChecked()} is true. 
    * 
    * @param d The Drawable to use for the checkmark. 
    */ 
    public void setCheckMarkDrawable(Drawable d) { 
     if (mCheckMarkDrawable != null) { 
      mCheckMarkDrawable.setCallback(null); 
      unscheduleDrawable(mCheckMarkDrawable); 
     } 
     if (d != null) { 
      d.setCallback(this); 
      d.setVisible(getVisibility() == VISIBLE, false); 
      d.setState(CHECKED_STATE_SET); 
      setMinHeight(d.getIntrinsicHeight()); 

      mCheckMarkWidth = d.getIntrinsicWidth(); 
      mPaddingRight = mCheckMarkWidth + mBasePaddingRight; 
      d.setState(getDrawableState()); 
     } else { 
      mPaddingRight = mBasePaddingRight; 
     } 
     mCheckMarkDrawable = d; 
     requestLayout(); 
    } 

    @Override 
    public void setPadding(int left, int top, int right, int bottom) { 
     super.setPadding(left, top, right, bottom); 
     mBasePaddingRight = mPaddingRight; 
    } 

    @Override 
    protected void onDraw(Canvas canvas) { 
     super.onDraw(canvas); 

     final Drawable checkMarkDrawable = mCheckMarkDrawable; 
     if (checkMarkDrawable != null) { 
      final int verticalGravity = getGravity() & Gravity.VERTICAL_GRAVITY_MASK; 
      final int height = checkMarkDrawable.getIntrinsicHeight(); 

      int y = 0; 

      switch (verticalGravity) { 
       case Gravity.BOTTOM: 
        y = getHeight() - height; 
        break; 
       case Gravity.CENTER_VERTICAL: 
        y = (getHeight() - height)/2; 
        break; 
      } 

      int right = getWidth(); 
      checkMarkDrawable.setBounds(
        right - mCheckMarkWidth - mBasePaddingRight, 
        y, 
        right - mBasePaddingRight, 
        y + height); 
      checkMarkDrawable.draw(canvas); 
     } 
    } 

    @Override 
    protected int[] onCreateDrawableState(int extraSpace) { 
     final int[] drawableState = super.onCreateDrawableState(extraSpace + 1); 
     if (isChecked()) { 
      mergeDrawableStates(drawableState, CHECKED_STATE_SET); 
     } 
     return drawableState; 
    } 

    @Override 
    protected void drawableStateChanged() { 
     super.drawableStateChanged(); 

     if (mCheckMarkDrawable != null) { 
      int[] myDrawableState = getDrawableState(); 

      // Set the state of the Drawable 
      mCheckMarkDrawable.setState(myDrawableState); 

      invalidate(); 
     } 
    } 

    @Override 
    public boolean dispatchPopulateAccessibilityEvent(AccessibilityEvent event) { 
     boolean populated = super.dispatchPopulateAccessibilityEvent(event); 
     if (!populated) { 
      event.setChecked(mChecked); 
     } 
     return populated; 
    } 
} 

您是onDraw有修改。和simple_list_item_single_choice.xml修改。

ex。

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