Question

我在andorid中写了一个简单的代码

package com.hello.stringtest;

import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

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

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });
        String x = "\r\nHello\r\nHello1\r\nHello2";
        Log.i("Hello", x);
        Toast.makeText(this,x,Toast.LENGTH_LONG).show();
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}

当我运行这个应用程序时，我希望在Log行中分开你好 Hello1 Hello2

但是Logcat表中没有任何内容。任何人都可以解释为什么它没有在Logcat中显示。

Answer 1

当我尝试使用代码时

    Log.i("ACTIVITY1", "\rCreated");
    Log.i("ACTIVITY2", "\nCreated");

只有ACTIVITY2出现在Logcat中。我想你的问题与\ r \ n有关。从String x中删除\ r \ n。尝试\ n而不是。

另见this。 \ r \ n似乎适用于旧的Mac OS版本。

Answer 2

这是因为默认情况下Log.i与log.d相比优先级较低。要检查它，将logcat窗口更改为来自debug的信息，您可以获得优先级的完整参考

The priority is one of the following character values, ordered from lowest to highest priority:
V — Verbose (lowest priority)
D — Debug
I — Info
W — Warning
E — Error
F — Fatal
S — Silent (highest priority, on which nothing is ever printed)

此链接也可能有用 http://developer.android.com/tools/debugging/debugging-log.html#startingLogcat

Log.i未在代码中显示

2 个答案: