动态更新TabWidget图标？

Question

是否可以更新 TabWidget 图标/指示器？如果是这样，当您通过意图创建 TabContent 时如何？

感谢 @Bart 的编辑，并给出答案

通用代码：

MainActivity:

public class TestActivity extends TabActivity {

public int i;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    //TabHost mTabHost = (TabHost) findViewById(android.R.id.tabhost);

    TabHost mTabHost = getTabHost();

    mTabHost.addTab(mTabHost.newTabSpec("tab1").setContent(
            new Intent(this, OneActivity.class)).setIndicator("One"));
    mTabHost.addTab(mTabHost.newTabSpec("tab2").setContent(
            new Intent(this, TwoActivity.class)).setIndicator("Two"));

    changeTitle(0, 20);
}

public void changeTitle(int cnt, int i){
    View v = getTabWidget().getChildAt(cnt);
    TextView tv = (TextView) v.findViewById(android.R.id.title);
    tv.setText("One ("+i+")");
}

}

OneActivity (ChildActivity):

public class OneActivity extends Activity {
TextView tv;
Button btn;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.one);

    tv = (TextView) findViewById(R.id.tv);
    btn = (Button) findViewById(R.id.btn);

    btn.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {

            int i = Integer.parseInt((String) tv.getText());
            i++;
            tv.setText(""+i);

             TestActivity parent = OneActivity.this.getParent();
             parent.changeTitle(0,i);

        }
    });
}

}

我想在选项卡标题中显示数字

Answer 1

给定标题和图标的数组

for (int i = 0; i < numTabs; i++ ) {
    TabSpec spec = host.newTabSpec(String.valueOf(i)); //sets tab index
    Drawable icon = res.getDrawable(icons[i]);  //sets the icon
    // set tab text and icon
    spec.setIndicator(titles[i], icon);  //sets the title

    host.addTab(spec);
}

Answer 2

尝试像这样获取 imageView

ImageView v = (ImageView)tabActivity.getTabHost().getTabWidget().getChildTabViewAt(i).findViewById(android.R.id.icon);

v.setImageDrawable(getResources().getDrawable(R.drawable.newIcon));

Answer 3

这是可能的，但有点棘手：

ViewGroup vg = (ViewGroup) getTabHost().getTabWidget().getChildAt(0);
TextView tv = (TextView) vg.getChildAt(1);

调用 getChildAt() 时应该注意索引。最好的方法始终是调试和检查。

从 1.6 开始，TabWidget 有一个 getChildTabViewAt 方法，借助它，您可以跳过第一行并编写：

ViewGroup vg = (ViewGroup) getTabHost().getTabWidget().getChildTabViewAt(0);

---

I attach also source code of Android SDK to show how TabWidget icons are built:

View tabIndicator = inflater.inflate(R.layout.tab_indicator, 
mTabWidget, // tab widget is the parent
false); // no inflate params

final TextView tv = (TextView) tabIndicator.findViewById(R.id.title);
tv.setText(mLabel);
final ImageView iconView = (ImageView) tabIndicator.findViewById(R.id.icon); 
iconView.setImageDrawable(mIcon);

正如你所看到的，它包含一个TextView和ImageView。