我需要将UI元素引用到非活动类别,无论该元素是什么类型。然后将 onTouchEvent 附加到该元素中的非活动类中。
我该怎么做?我搜索了互联网,但没有找到任何有帮助的东西。
您沿构造函数或方法调用传递上下文。示例:
MyNonActivityClass myObject = new MyNonActivityClass(getActivity());
mynonActivityClass
import android.content.Context;
import your.package.name.R; // notice the R you should add your package
// infront of R it should be something like
// com.example.myapp.R
public class MyNonActivityClass{
private Context context;
public MyNonActivityClass(Context c){
if(context instanceof MyActivityClass){
this.context=c;
}
/** you can do multi if else statements for multi activity classes **/
}
private void someMethodToHandleUi(){
View v = ((MyActivityClass)context).findViewById(R.id.myView);
v.setOnTouchListener(new OnTouchListener(){
// rest of your code
});
}
}
我找到了不需要上下文的解决方案,或者如果条件,我所要做的就是将元素引用到类作为对象,而不是使用fealReference将参考引用。<<<<<<<<<<<<<</p>
这是代码:
public class NonActivityClass{
private WeakReference<Object> target;
public NonActivityClass(Object target){
this.target = new WeakReference<Object>(target);
}
@Nullable
public Object getTarget() {
return target == null ? null : target.get();
}
public void doSomethingWithUIElement(){
View view = (View) getTarget();
view.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
return true;
}
});
}
}