列表视图中的单选按钮

Question

我在列表视图formate中显示sting列表，我使用了默认列表视图并使用simple_list_item_single_choice放置了一个单选按钮。但是这显示右侧的单选按钮，我想在左侧显示单选按钮。是任何可能的使用默认列表视图显示左侧的单选按钮

Answer 1

simple_list_item_single_choice.xml使用CheckedTextView类

这里是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" 
    /> 

您需要为您的需要自定义XML和使用CheckBox来实现你的目标 这里是你的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" 
    /> 

只需在代码中使用custom.xml代替simple_list_item_single_choice.xml即可。

希望它可以帮助你。

Answer 2

这是不可能的，默认情况下单选按钮在右侧。如果你想要它在左边，那么你应该从SDK中获取simple_list_item_single_choice.xml布局的源代码并进行适当的更改，然后使用此自定义布局而不是默认布局。

Answer 3

simple_list_item_single_choice使用CheckedTextView类。

<?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类是android.widget包。

下面这个类的来源。

/*

* 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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