处理程序不延迟- Android Studio Java

Question

我正在做一个项目。我的程序显示视频的视屏，并从excel文件中获取值。我很难一个一个地表示这些值。我正在尝试使用一些延迟方法。我已经使用线程。sleep和SystemClock。睡眠方法，但会冻结整个应用程序和手机。现在我正在尝试使用处理程序方法。我没有收到任何错误，但没有延迟。我把我的代码放在下面。

如果有人能帮我解决这个问题，我将非常高兴。

package com.example.exceldeneme;
import androidx.appcompat.app.AppCompatActivity;
import android.net.Uri;
import android.os.Bundle;
import android.os.Handler;
import android.os.Looper;
import android.widget.MediaController;
import android.widget.VideoView;
import android.os.SystemClock;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.Arrays;
import java.lang.String;
import java.util.Random;
import java.util.concurrent.TimeUnit;
import java.util.List;

public class MainActivity<number_cars> extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
VideoView videoView = findViewById(R.id.video_view);
Button  button = findViewById(R.id.button);
TextView text_cars = findViewById(R.id.textEmpty);
TextView text_total_lots = findViewById(R.id.textTotalLots);
readData();
int number_of_park = 100;
text_total_lots.setText(String.valueOf(number_of_park));
int counter = 0;
String videoPath = "android.resource://" + getPackageName() + "/" + R.raw.camera_out;
Uri uri = Uri.parse(videoPath);
videoView.setVideoURI(uri);
MediaController mediaController = new MediaController(this);
videoView.setMediaController(mediaController);
mediaController.setAnchorView(videoView);

for (String i : number_of_cars.get(0)){
counter = counter + 1 ;
}
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
int counter = 0;
for (String i : number_of_cars.get(0)){
counter = counter + 1 ;
}
for (int i = 1; i < counter-1;i= i +1){
String count_park = number_of_cars.get(0)[i];
new Handler(Looper.getMainLooper()).postDelayed(new Runnable() {
@Override
public void run() {
text_cars.setText(count_park);
}
}, 1000);

//SystemClock.sleep(1000); //ms
Log.d("Selam","SORUN YOK");
}
}
});

}

private ArrayList<String[]> number_of_cars = new ArrayList<String[]>();
private void readData() {
InputStream is = getResources().openRawResource(R.raw.numberofcars);
BufferedReader reader = new BufferedReader(
new InputStreamReader(is, Charset.forName("UTF-8"))
);
String line = "";
try {
while(((line = reader.readLine()) != null)) {
String[] tokens = line.split(",");
number_of_cars.add(tokens);
Log.d("MyActivity","Just created"+ Arrays.toString(tokens));
}
}
catch (IOException e) {
Log.wtf("MyActivity","Error reading data file on line" + line, e);
e.printStackTrace();
}
}
}

Answer 1

对于您可能想要的孤立问题:

new Handler(Looper.getMainLooper()).postDelayed(new Runnable() {
@Override
public void run() {
text_cars.setText(count_park);
}
}, 1000 * i);

但是你真的应该有一个单独的实例Handler，并将所有Runnable对象发布到它，并有一种方法来删除所有挂起的Runnable，如果ui被销毁时使用:Handler::removeCallbacksAnMessages(null)在相关的钩子方法中，如onDestroy。