我运行了一个应用程序来获取手机的Mac地址,我完成了代码,编译时没有错误,但如果我点击main_activity,预览下会出现错误:找不到以下类:
-Textview(更改为Textview,修复构建路径,编辑XML)。
实际上我没有输出。
这是主要活动:
package com.example.app1;
import android.bluetooth.BluetoothAdapter;
import android.content.Context;
import android.net.wifi.WifiManager;
import android.provider.Settings;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.telephony.TelephonyManager;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
TextView tvUIDS;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tvUIDS = (TextView) findViewById(R.id.tv_uids);
StringBuilder sb = new StringBuilder();
TelephonyManager telMan = (TelephonyManager) getSystemService(TELEPHONY_SERVICE);
sb.append("IMEI: " + telMan.getDeviceId() + "n");
sb.append("Android ID: " + Settings.Secure.getString(getContentResolver(), Settings.Secure.ANDROID_ID) + "n");
WifiManager wm = (WifiManager) getSystemService(Context.WIFI_SERVICE);
String mac_adr = wm.getConnectionInfo().getMacAddress();
if (mac_adr != null) {
sb.append("WLAN MAC Address: " + mac_adr + "n");
} else {
sb.append("WLAN MAC Address: not supported on this devicen");
}
BluetoothAdapter ba = BluetoothAdapter.getDefaultAdapter();
if (ba != null) {
sb.append("Bluetooth Address: " + ba.getAddress() + "n");
} else {
sb.append("Bluetooth Address: not supported on this devicen");
}
tvUIDS.setText(sb.toString());
}
}
这就是activity_main.xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<Textview
android:id="@+id/tv_uids"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Mac Address" />
</RelativeLayout>
这是舱单:
<?xml version="1.0" encoding="utf-8"?>
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.BLUETOOTH" />
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
对不起,我是应用程序的新手。我该如何解决?
谢谢!
找不到以下类:-Textview(更改为TextView,修复构建路径,编辑XML)
这意味着您的xml中有不正确的标记或无法识别的标记。activity_main.xml中存在以下错误的xml:
<Textview
android:id="@+id/tv_uids"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Mac Address" />
应该是:
<TextView
android:id="@+id/tv_uids"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Mac Address" />
正确的标签是TextView
而不是Textview
。