android - 从线程传递消息以更新 UI

Question

我为文件浏览器创建了一个新线程。线程读取目录的内容。我想要做的是更新 UI 线程以绘制文件和文件夹的图形表示。我知道我无法从新线程中更新 UI，所以我想做的是:

当文件扫描线程遍历目录文件和文件夹时，将文件路径字符串传递回 UI 线程。 UI 线程中的处理程序然后绘制传回文件的图形表示。

public class New_Project extends Activity implements Runnable {

    private Handler handler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            Log.d("New Thread","Proccess Complete.");
            Intent intent = new Intent();
            setResult(RESULT_OK, intent);
            finish();
        }
    };


    public void fileScanner(){
        //if (!XMLEFunctions.canReadExternal(this)) return;
        pd = ProgressDialog.show(this, "Reading Directory.",
                "Please Wait...", true, false);

        Log.d("New Thread","Called");
        Thread thread = new Thread(this);
        thread.start();
    }


    public void run() {
        Log.d("New Thread","Reading Files");
        getFiles();
        handler.sendEmptyMessage(0);
    }


    public void getFiles() {
        for (int i=0;i<=allFiles.length-1;i++){
            //I WANT TO PASS THE FILE PATH BACK TU A HANDLER IN THE UI
            //SO IT CAN BE DRAWN.
            **passFilePathBackToBeDrawn(allFiles[i].toString());**
        } 
    }

}

Answer 1

似乎传递简单消息是基于 int 的...我需要做的是传递一个 Bundle

using Message.setData(Bundle) and Message.getData(Bundle)

好开心=0)

//Function From Within The Thread

public void newProjectCreation() {

Message msg =  new Message();
Bundle bundle = new Bundle();

bundle.putString("Test", "test value");
msg.setData(bundle);

handler2.sendMessage(msg);
}

//Handler in The UI Thread Retreieves The Data
//And Can Update the GUI as Required

private Handler handler2 = new Handler() {
    @Override
    public void handleMessage(Message msg) {

    Bundle bundle = msg.getData();
    Toast.makeText(New_Project.this,bundle.getString("Test"),Toast.LENGTH_SHORT).show();

}

};