在 Android 应用程序的屏幕上显示日志消息

Question

是否可以在 Android 应用程序的屏幕上显示日志消息（我使用 android.util.Log 打印）？

还有其他更好的方法来在屏幕上输出行吗？

类似System.out.println?

Answer 1

是的零4

您尝试做的是在 android shell 上删除“logcat”命令并将命令输出作为输出流。link 将帮助您。

Answer 2

就像其他人建议的那样，您可以使用 log cat。如果您正在使用模拟器或调试设备，您可以使用adb logcat 来查看消息。在 Eclipse 调试透视图中，有一个窗口可以为您执行此操作。

另一种不附加调试器的方法是使用CatLog - Logcat Reader 应用程序。

Answer 3

我使用“android.widget.Toast.makeText(Context context, CharSequence text, int duration)”来执行您所要求的操作。似乎是在屏幕上获取一些快速消息并使其自动消失的最简单方法（基于最后一个参数）。

:-)

Answer 4

嗯，有一个解决方案可以使用this lib 在屏幕上记录您想要的任何内容。它对我不起作用，所以我开发了自己的解决方案，您可以找到它的示例here。真的很简单，在你的项目中添加一个类 OnScreenLog

package br.com.ideiageni.onscreenlogSample;

import android.app.Activity;
import android.graphics.Color;
import android.os.Handler;
import android.view.MotionEvent;
import android.view.View;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import android.widget.TextView;


/**
 * Created by ariel on 07/07/2016.
 */
    public class OnScreenLog {
    private static int timeoutTime = 1000;
    private static TextView tvLog;
    private static int logCount = 0;
    private static int logCountMax = 30;
    private static String[] logs = new String[logCountMax];
    private static int cntClicks = 0;
    private static boolean visibility = false;
    private static Activity activity;
    private int maxClicks = 5;

    public OnScreenLog(){}

    public OnScreenLog(Activity activity, int ViewID){
        OnScreenLog.activity = activity;
        tvLog = new TextView(activity.getApplicationContext());
        maintainLog("Log is working");
        tvLog.setLayoutParams(new RelativeLayout.LayoutParams(
            RelativeLayout.LayoutParams.WRAP_CONTENT,
            RelativeLayout.LayoutParams.WRAP_CONTENT));
        tvLog.setTextColor(Color.BLACK);
        tvLog.setBackgroundColor(Color.LTGRAY);
        tvLog.setAlpha((float) 0.4);

        View v = null;
        LinearLayout linearLayout;
        RelativeLayout relativeLayout;
        try {
            linearLayout = (LinearLayout) activity.findViewById(ViewID);
        } catch (ClassCastException e) {linearLayout = null;};

        try {
            relativeLayout = (RelativeLayout) activity.findViewById(ViewID);
        } catch (ClassCastException e) {relativeLayout = null;};
        if(linearLayout != null) {
            linearLayout.addView(tvLog);
            v = linearLayout;
        } else if(relativeLayout != null) {
            relativeLayout.addView(tvLog);
            v = relativeLayout;
        }

        if(v != null) {
            v.setOnTouchListener(new View.OnTouchListener() {
                @Override
                public boolean onTouch(View v, MotionEvent event) {
                    switch (event.getAction()) {
                        case MotionEvent.ACTION_DOWN:
                            cntClicks++;
                            timerHandler.removeCallbacks(rTimeout);
                            timerHandler.postDelayed(rTimeout, timeoutTime);

                            if (cntClicks > maxClicks-1) {
                                setLogVisible(!visibility);
                                timerHandler.removeCallbacks(rTimeout);
                                cntClicks = 0;
                            }
                            break;

                    }
                    return false;
                }
            });
        }

    }

    public void log (String text){
        String logText = text;
        maintainLog(logText);
    }

    public void log (int text){
        String logText = String.valueOf(text);
        maintainLog(logText);
    }

    public void log (int[] text){
        StringBuilder builder = new StringBuilder();
        for (int i : text) {
            builder.append(i);
            builder.append("-");
        }
        String logText = builder.toString();
        maintainLog(logText);
    }

    public void log (byte[] text){
        StringBuilder builder = new StringBuilder();
        for (int i : text) {
            builder.append(i);
            builder.append("-");
        }
        String logText = builder.toString();
        maintainLog(logText);
    }

    private void maintainLog(String newText){
        String logText = "";
        if(logCount<logCountMax) logCount++;
        for(int i=logCount-1; i>0; i--){
            logs[i] = logs[i-1];
        }
        logs[0] = newText;
        for(int i=0; i<logCount; i++){
            if(i<logCount-1) logText+=logs[i]+System.getProperty("line.separator");
            else logText+=logs[i];
        }
        tvLog.setText(logText);
    }

    public void clearLog(){
        tvLog.setText("");
    }

    public void setLogVisible(boolean visibility){
        if(visibility) tvLog.setVisibility(View.VISIBLE);
        else tvLog.setVisibility(View.INVISIBLE);
        OnScreenLog.visibility = visibility;
    }

    public static int getLogCountMax() {
        return logCountMax;
    }

    public static void setLogCountMax(int logCountMax) {
        OnScreenLog.logCountMax = logCountMax;
        logs = new String[logCountMax];
    }

    public int getMaxClicks() {
        return maxClicks;
    }

    public void setMaxClicks(int maxClicks) {
        this.maxClicks = maxClicks;
    }

    Handler timerHandler = new Handler();
    Runnable rTimeout = new Runnable() {

        @Override
        public void run() {
            cntClicks = 0;
        }
    };
}

那么，例如：

public class Activity1 extends AppCompatActivity {

private OnScreenLog log;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_1);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    log = new OnScreenLog(this, R.id.content_1);
    log.log("Started log on Activity 1");

    FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
    fab.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Intent intent = new Intent(getApplicationContext(), Activity2.class);
            startActivity(intent);
            log.log("Starting Activity 2");
            Snackbar.make(view, "Starting Activity 2", Snackbar.LENGTH_LONG)
                    .setAction("Action", null).show();
        }
    });
}

其中 R.id.content_1 是您的活动的主要 LinearLayout 或 RelativeLayout 的名称。

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout 
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/content_1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:context="br.com.ideiageni.onscreenlogSample.Activity1"
tools:showIn="@layout/activity_1">

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Activity 1!" />

</RelativeLayout>

这两种解决方案都不会打印当前的日志消息，因此您需要告诉它记录以筛选您今天在当前日志上记录的相同信息。

工作尚未完成，但可供有需要的人使用。缺少一些有关如何使用的说明。欢迎提出建议。