相关疑难解决方法(0)

我想动态更改android中进度条的背景颜色.我按照本教程页面末尾附近的"奖励"部分进行了操作:

http://colintmiller.com/2010/10/how-to-add-text-over-a-progress-bar-on-android/

它会改变颜色,但只改变一次.如果多次调用,进度条将消失.这是代码.

这是进度条定义:

<ProgressBar android:id="@+id/progress_bar" android:layout_width="fill_parent"
    android:layout_height="wrap_content" style="@android:style/Widget.ProgressBar.Horizontal"
    android:layout_marginRight="5dp" />

这是res/drawable/green_progress.xml中的可绘制定义:

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">

<item android:id="@android:id/background">
    <shape>
        <corners android:radius="5dip" />
        <gradient
                android:startColor="#ff9d9e9d"
                android:centerColor="#ff5a5d5a"
                android:centerY="0.75"
                android:endColor="#ff747674"
                android:angle="270"
        />
    </shape>
</item>

<item android:id="@android:id/secondaryProgress">
    <clip>
        <shape>
            <corners android:radius="5dip" />
            <gradient
                    android:startColor="#80ffd300"
                    android:centerColor="#80ffb600"
                    android:centerY="0.75"
                    android:endColor="#a0ffcb00"
                    android:angle="270"
            />
        </shape>
    </clip>
</item>
<item
    android:id="@android:id/progress">
    <clip>
        <shape>
            <corners
                android:radius="5dip" />
            <gradient
                    android:startColor="@color/greenStart"
                    android:centerColor="@color/greenMid"
                    android:centerY="0.75"
                    android:endColor="@color/greenEnd"
                    android:angle="270"
            />
        </shape>
    </clip>
</item>

</layer-list>

rex/values/colors.xml的ene条目:

<color name="greenStart">#ff33dd44</color>
<color name="greenMid">#ff0A8815</color>
<color name="greenEnd">#ff1da130</color>

最后,在代码中:

m_bar.setProgressDrawable(getResources().getDrawable(R.drawable.green_progress));  

同样,问题是它第一次起作用,但随后使条形消失.

使用setProgressDrawable了ProgressBar具有自定义颜色不给我们以正确的方式工作.我们在a的行中使用progressbars ListView,但仅当列表中有多个元素时才会显示进度.如果是一个元素,则进度条为空.

CursorAdapter.java:

public class CursorAdapter extends SimpleCursorAdapter {
    public CursorAdapter(Context context, int layout, Cursor c, String[] from,
            int[] to) {
        super(context, layout, c, from, to);
    }

    public void bindView(View view, Context context, Cursor cursor) {
        super.bindView(view, context, cursor);
        updateProgressbar(view, cursor);
    }

    /**
     * This method updates the progressbar using the "numberpages" and
     * "currentpage" values. 
     */
    private void updateProgressbar(View view, Cursor cursor) {
        ProgressBar progressBar = (ProgressBar) view
                .findViewById(R.id.progressbarHorizontal);

        progressBar.setProgressDrawable(view.getResources().getDrawable(
                R.drawable.greenprogress));

        progressBar.setMax(cursor.getInt(cursor.getColumnIndex("numberpages")));
        progressBar.setProgress(cursor.getInt(cursor
                .getColumnIndex("currentpage"))); …