ListView 项目背景地狱 [英] ListView item background hell

问题描述

因为复选框不是我的项目的一个选项，所以我希望可检查对象在被选中时有一个背景.从 2.3 开始我还没有设法解决这个问题.选择是正确的，但我在屏幕上看到的不是.随机行的随机颜色..

Because checkbox isnt an option for my project I want the checkable to have a background when checked.Supporting from 2.3 i havent manage to solve this problem yet. Selection is correct but what i see at screen isnt.Random color at random row..

拳头我有这个

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_pressed="true" android:drawable="@drawable/abs__list_selector_holo_light" />
    <item android:state_checked="true" android:drawable="@drawable/abs__list_selector_holo_light" />
    <item android:state_selected="true" android:drawable="@drawable/abs__list_selector_holo_light" />
       <item  android:drawable="@drawable/abs__list_selector_holo_light" />
</selector>

-

 public class CheckableRelativeLayout extends RelativeLayout implements
        Checkable {

    private boolean isChecked;
    private List<Checkable> checkableViews;


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

    public CheckableRelativeLayout(Context context, AttributeSet attrs,
            int defStyle) {
        super(context, attrs, defStyle);
        initialise(attrs);
    }

    public CheckableRelativeLayout(Context context, AttributeSet attrs) {
        super(context, attrs);
        initialise(attrs);
    }

    public CheckableRelativeLayout(Context context, int checkableId) {
        super(context);
        initialise(null);
    }

    /*
     * @see android.widget.Checkable#isChecked()
     */
    public boolean isChecked() {
        return isChecked;
    }

    /*
     * @see android.widget.Checkable#setChecked(boolean)
     */
    public void setChecked(boolean isChecked) {
        this.isChecked = isChecked;
        for (Checkable c : checkableViews) {
            c.setChecked(isChecked);
        }
    }

    /*
     * @see android.widget.Checkable#toggle()
     */
    public void toggle() {
        this.isChecked = !this.isChecked;
        for (Checkable c : checkableViews) {
            c.toggle();
        }
    }

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

        final int childCount = this.getChildCount();
        for (int i = 0; i < childCount; ++i) {
            findCheckableChildren(this.getChildAt(i));
        }
    }

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

    @Override
    public boolean performClick() {
        toggle();
        return super.performClick();
    }


    /**
     * Read the custom XML attributes
     */
    private void initialise(AttributeSet attrs) {
        this.isChecked = false;
        this.checkableViews = new ArrayList<Checkable>(5);
    }

    /**
     * Add to our checkable list all the children of the view that implement the
     * interface Checkable
     */
    private void findCheckableChildren(View v) {
        if (v instanceof Checkable) {
            this.checkableViews.add((Checkable) v);
        }

        if (v instanceof ViewGroup) {
            final ViewGroup vg = (ViewGroup) v;
            final int childCount = vg.getChildCount();
            for (int i = 0; i < childCount; ++i) {
                findCheckableChildren(vg.getChildAt(i));
            }
        }
    }
}

我得到的是这个

推荐答案

这是一个关于制作 Checkable 视图的简洁示例:

Here's a clean example on making a Checkable View:

import android.R;
import android.content.Context;
import android.util.AttributeSet;
import android.widget.Checkable;
import android.widget.LinearLayout;

public class ActivatedLinearLayout extends LinearLayout implements Checkable{

    public static final int[] CHECKED_STATE = {R.attr.state_checked};
    private boolean mChecked;

    public ActivatedLinearLayout(Context context) {
        super(context);
    }

    public ActivatedLinearLayout(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

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


    @Override
    public void setChecked(boolean b) {
        mChecked = b;
        refreshDrawableState();
    }

    @Override
    public boolean isChecked() {
        return mChecked;
    }

    @Override
    public void toggle() {
        mChecked = !mChecked;
        refreshDrawableState();
    }

    @Override
    protected int[] onCreateDrawableState(int extraSpace) {
        int[] states =  super.onCreateDrawableState(extraSpace + 1);
        if (mChecked){
            mergeDrawableStates(states, CHECKED_STATE);
        }
        return states;
    }


}

和选择器:

<?xml version="1.0" encoding="utf-8"?>

<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_checked="true" android:drawable="@drawable/checked"/>
<item android:drawable="@drawable/unchecked"/>
</selector>

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