如何为 TabHost 背景动态更改 shapedrawable 颜色?
How to change shapedrawable color dynamically for TabHost background?
我有一个 TabHost,我在其中使用形状 xml 使其看起来像这样:
我这样定义TabHost背景:
private void setTabColor(TabHost tabHost) {
try {
for (int i = 0; i < tabHost.getTabWidget().getChildCount(); i++) {
tabHost.getTabWidget().getChildAt(i).setBackgroundResource(R.drawable.strib_tab);
}
} catch (ClassCastException e) {
}
}
其中 strib_tab 是:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="@drawable/line_pressed" android:state_selected="true"/>
<item android:drawable="@drawable/line"/>
</selector>
和line_pressed是:
<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android" >
<item>
<shape android:shape="rectangle" >
<stroke
android:width="5dip"
android:color="@color/blue_bg" />
<padding
android:bottom="0dip"
android:left="0dip"
android:right="0dip"
android:top="0dip" />
</shape>
</item>
<item
android:bottom="5dp"
android:top="0dp">
<shape android:shape="rectangle" >
<solid android:color="#FFFFFF" />
</shape>
</item>
</layer-list>
行是:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item>
<shape>
<solid android:color="@android:color/transparent" />
</shape>
</item>
</selector>
如何动态更改 line_pressed 中颜色为 blue_bg 的形状的颜色?
您似乎无法修改 StateListDrawable
,但是您可以轻松地创建新的。
至于LayerDrawable
,可以很容易地操纵。
代码说话更好,所以这里是:
Resources r = getResources();
// Modify the LayerDrawable (line_pressed)
LayerDrawable ld = (LayerDrawable) r.getDrawable(R.drawable.line_pressed);
GradientDrawable gradient = (GradientDrawable) ld
.findDrawableByLayerId(R.id.stroke);
// Set a custom stroke (width in pixels)
gradient.setStroke(5, Color.RED);
// Create a new StateListDrawable
StateListDrawable newStripTab = new StateListDrawable();
newStripTab.addState(new int[] { android.R.attr.state_selected }, ld);
newStripTab.addState(new int[0], r.getDrawable(R.drawable.line));
tabHost.getTabWidget().getChildAt(i).setBackgroundResource(newStripTab);
备注:
我用的是自定义的line_pressed,所以很容易找到特定的图层:
<layer-list xmlns:android="http://schemas.android.com/apk/res/android" >
<item android:id="@+id/stroke">
<shape android:shape="rectangle" >
<stroke
android:width="5dip"
android:color="#000" />
...
</shape>
</item>
...
</layer-list>
此代码未经实际测试,但应该可以工作或至少提供一些关于如何实现此目的的见解。
我有一个 TabHost,我在其中使用形状 xml 使其看起来像这样:
我这样定义TabHost背景:
private void setTabColor(TabHost tabHost) {
try {
for (int i = 0; i < tabHost.getTabWidget().getChildCount(); i++) {
tabHost.getTabWidget().getChildAt(i).setBackgroundResource(R.drawable.strib_tab);
}
} catch (ClassCastException e) {
}
}
其中 strib_tab 是:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="@drawable/line_pressed" android:state_selected="true"/>
<item android:drawable="@drawable/line"/>
</selector>
和line_pressed是:
<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android" >
<item>
<shape android:shape="rectangle" >
<stroke
android:width="5dip"
android:color="@color/blue_bg" />
<padding
android:bottom="0dip"
android:left="0dip"
android:right="0dip"
android:top="0dip" />
</shape>
</item>
<item
android:bottom="5dp"
android:top="0dp">
<shape android:shape="rectangle" >
<solid android:color="#FFFFFF" />
</shape>
</item>
</layer-list>
行是:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item>
<shape>
<solid android:color="@android:color/transparent" />
</shape>
</item>
</selector>
如何动态更改 line_pressed 中颜色为 blue_bg 的形状的颜色?
您似乎无法修改 StateListDrawable
,但是您可以轻松地创建新的。
至于LayerDrawable
,可以很容易地操纵。
代码说话更好,所以这里是:
Resources r = getResources();
// Modify the LayerDrawable (line_pressed)
LayerDrawable ld = (LayerDrawable) r.getDrawable(R.drawable.line_pressed);
GradientDrawable gradient = (GradientDrawable) ld
.findDrawableByLayerId(R.id.stroke);
// Set a custom stroke (width in pixels)
gradient.setStroke(5, Color.RED);
// Create a new StateListDrawable
StateListDrawable newStripTab = new StateListDrawable();
newStripTab.addState(new int[] { android.R.attr.state_selected }, ld);
newStripTab.addState(new int[0], r.getDrawable(R.drawable.line));
tabHost.getTabWidget().getChildAt(i).setBackgroundResource(newStripTab);
备注:
我用的是自定义的line_pressed,所以很容易找到特定的图层:
<layer-list xmlns:android="http://schemas.android.com/apk/res/android" > <item android:id="@+id/stroke"> <shape android:shape="rectangle" > <stroke android:width="5dip" android:color="#000" /> ... </shape> </item> ... </layer-list>
此代码未经实际测试,但应该可以工作或至少提供一些关于如何实现此目的的见解。