Question

我为罗嗦的标题道歉 - 我不确定如何准确地说出这一点。我正在尝试（在我的onCreate（）方法中）：

- 初始化一些事情

- 在我从后端加载一些数据时显示进度对话框

- 清除进度对话框，然后继续使用代码

我理解典型的进度对话解决方案是一个asynctask，我尝试过使用它（见下文）。但是，这并不像我想的那样锁定代码执行。 lwpd.execute（）之后的代码依赖于已经发生的加载。我是不是太复杂了？做我想做的正确方法是什么？

供参考，我的Asynctask实现：

public class LoadWithProgressDialog extends AsyncTask<Void, Void, Boolean>{
    private ProgressDialog pd; //the progress dialog
    private String title; //the title of the progress dialog
    private String  message; //the body of the progress dialog
    private Runnable task; //contains the code we want to run in the background
    private Context c;


    public LoadWithProgressDialog(Context context,String t, String m,Runnable r){
        super();
        c = context;
        task = r;
        title = t;
        message = m;
    }

    @Override
    protected void onPreExecute(){
        pd = ProgressDialog.show(c,title, message, false, false);
    }

    @Override
    protected Boolean doInBackground(Void... params) {
        task.run();
        return true;
    }
   @Override
   protected void onPostExecute(Boolean result) {
            pd.dismiss(); 
   }





}

和

 super.onCreate(savedInstanceState);
            setContentView(R.layout.main);

            //initialize variables


            LoadWithProgressDialog lwpd = new LoadWithProgressDialog(this,"Loading","Loading Truck Data", new Runnable() {
                public void run(){
                    //code that loads things
                }
            });
            lwpd.execute();

//continue on with my code

}

Answer 1

您应该将进度对话框保留在异步任务中。

加载数据后要执行的任何代码都可以放在onPostExecute方法中！

public LoadWithProgressDialog(Context context,String t, String m,Runnable r){
    super();
    c = context;
    task = r;
    title = t;
    message = m;
}

@Override
protected void onPreExecute(){
    pd = ProgressDialog.show(c,title, message, false, false);
}

@Override
protected Boolean doInBackground(Void... params) {
    task.run();
    return true;
}
@Override
protected void onPostExecute(Boolean result) {
        pd.dismiss(); 

      // PUT YOUR CODE THAT YOU WANT TO RUN AFTER THE DATA HAS LOADED HERE!
}

Answer 2

不锁定代码执行是AsyncTask的重点。如果你想阻止代码执行，只需在主线程上创建一个ProgressDialog

在显示ProgressDialog +暂停代码执行时加载后台

2 个答案: