Android studio项目，按钮不起作用

Question

我当前正在执行Locator项目

但是，在我按此按钮时，“按此获取位置”的过程无法正常工作。它什么也不会做。

这里是MainActivity代码

package com.example.pc.locatorproject;

import android.Manifest;
import android.content.pm.PackageManager;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AppCompatActivity;
import android.text.Html;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

import com.google.android.gms.location.FusedLocationProviderClient;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;

import java.io.IOException;
import java.util.List;
import java.util.Locale;

public class MainActivity extends AppCompatActivity {
    TextView textView1, textView2, textView3, textView4, textView5;
    FusedLocationProviderClient fusedLocationProviderClient;
    Button btLocation;
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        btLocation = findViewById(R.id.bt_location);
        textView1 = findViewById(R.id.text_view1);
        textView2 = findViewById(R.id.text_view2);
        textView3 = findViewById(R.id.text_view3);
        textView4 = findViewById(R.id.text_view4);
        textView5 = findViewById(R.id.text_view5);

        fusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(this);

        btLocation.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (ActivityCompat.checkSelfPermission(MainActivity.this
                        , Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED){
                    getLocation();
                }
                else {
                    ActivityCompat.requestPermissions(MainActivity.this
                            , new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 44);
                }
        }
    });
    }
    private void getLocation() {
        fusedLocationProviderClient.getLastLocation().addOnCompleteListener(new OnCompleteListener<Location>() {
            @Override
            public void onComplete(@NonNull Task<Location> task) {
                Location location = task.getResult();
                    if (location != null){
                        try {
                            Geocoder geocoder = new Geocoder(MainActivity.this, Locale.getDefault());
                            List<Address> addresses = geocoder.getFromLocation(location.getLatitude(), location.getLongitude(), 1 );
                            textView1.setText(Html.fromHtml("<font color='#6200EE'><B>Latitude :</b><br></font>" + addresses.get(0).getLatitude()));
                            textView2.setText(Html.fromHtml("<font color='#6200EE'><B>Longitude :</b><br></font>" + addresses.get(0).getLongitude()));
                            textView3.setText(Html.fromHtml("<font color='#6200EE'><B>Country Name :</b><br></font>" + addresses.get(0).getCountryName()));
                            textView4.setText(Html.fromHtml("<font color='#6200EE'><B>Locality :</b><br></font>" + addresses.get(0).getLocality()));
                            textView5.setText(Html.fromHtml("<font color='#6200EE'><B>Address :</b><br></font>" + addresses.get(0).getAddressLine(0)));
                        } catch (IOException e) {
                            e.printStackTrace();
                        }
                    }
                    }
            });
        }
    }

这是XML代码

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

    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:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:padding="16dp"
    android:layout_gravity="center_horizontal"

    tools:context=".MainActivity">

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:id="@+id/bt_location"
        android:text="Press to get your location"
        />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:layout_marginTop="32dp">

        <TextView
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:id="@+id/text_view1"/>

        <TextView
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:id="@+id/text_view2"/>

    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:layout_marginTop="16dp">

        <TextView
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:id="@+id/text_view3"/>

        <TextView
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:id="@+id/text_view4"/>

    </LinearLayout>

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:id="@+id/text_view5"/>

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

    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:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:padding="16dp"
    android:layout_gravity="center_horizontal"

    tools:context=".MainActivity">

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:id="@+id/bt_location"
        android:text="Press to get your location"
        />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:layout_marginTop="32dp">

        <TextView
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:id="@+id/text_view1"/>

        <TextView
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:id="@+id/text_view2"/>

    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:layout_marginTop="16dp">

        <TextView
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:id="@+id/text_view3"/>

        <TextView
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:id="@+id/text_view4"/>

    </LinearLayout>

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:id="@+id/text_view5"/>

</LinearLayout>

这是build.gradle代码

apply plugin: 'com.android.application'

android {
    compileSdkVersion 29
    buildToolsVersion "29.0.3"

    defaultConfig {
        applicationId "com.example.pc.locatorproject"
        minSdkVersion 14
        targetSdkVersion 29
        versionCode 1
        versionName "1.0"
        multiDexEnabled true

        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }

}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.google.android.gms:play-services:12.0.1'
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
    implementation 'com.android.support:multidex:1.0.3'
}

[正常运行时，我希望按下“按此获取您的位置”按钮。它将显示5个详细信息，例如经度，纬度，地址，国家/地区和位置。但它没有显示。

请帮助我使“按一下以获取您的位置”按钮。

Answer 1

请确保在manifest中添加权限：

 <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>

支持运行时权限的设备是api级别为23或更高的设备，如果您正在较低版本的设备上进行测试，则不会触发该请求。