This document provides instructions and code samples for building a basic Android web app using Android Studio. It includes setting up the SDK, creating layout files with a WebView and ProgressBar, adding permissions and activities to the manifest, and adding listeners for downloads and the back button. Code samples are provided for setting WebView properties, displaying loading progress, and overriding the back button to go back in the webview history. The document also provides shortcuts for automatically formatting code on different operating systems.

1. 안드로이드 앱 개발 실습 【Web App】
1. Android Studio
1.1.SDK Manager
- Android API 27 | API Level 27 | Revision 3
2. Base Source
2.1. activity_main.xml (app/src/main/res/layout/activity_main.xml)
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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"
tools:context=“com.test.sample.MainActivity”>
<ProgressBar android:id="@+id/pro"
style="?android:attr/progressBarStyleHorizontal"
android:layout_width="fill_parent" android:layout_height="4dp"
android:layout_gravity="top" android:max="100"
android:paddingLeft="3dp"
android:paddingRight="3dp" />
<WebView
android:id="@+id/webview"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true" />
</android.support.constraint.ConstraintLayout>
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2. 2.2. MainActivity.java (app/src/main/java/<package name>/MainActivity)
public class MainActivity extends AppCompatActivity {
WebView mWebView = null;
ProgressBar progressBar = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// ** Remove TITLE BAR and Lock Screen ** //
// Remove title bar
this.requestWindowFeature(Window.FEATURE_NO_TITLE);
getSupportActionBar().hide();
// Set Screen lock (PORTRAIT)
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
setContentView(R.layout.activity_main);
// 02. Set WebView and ProgressBar
progressBar = (ProgressBar) this.findViewById(R.id.pro);
mWebView = (WebView)findViewById(R.id.webview);
mWebView.setWebViewClient(new WebViewClient());
WebSettings webSettings = mWebView.getSettings();
webSettings.setJavaScriptEnabled(true);
webSettings.setJavaScriptCanOpenWindowsAutomatically(true);
webSettings.setBuiltInZoomControls(true);
webSettings.setSupportZoom(true);
webSettings.setSupportMultipleWindows(true);
webSettings.setDisplayZoomControls(false);
webSettings.setLayoutAlgorithm(WebSettings.LayoutAlgorithm.SINGLE_COLUMN);
webSettings.setDefaultZoom(WebSettings.ZoomDensity.FAR);
mWebView.setWebChromeClient(new WebChromeClient(){
@Override
public void onProgressChanged(WebView view, int newProgress) {
super.onProgressChanged(view, newProgress);
progressBar.setProgress(newProgress);
}
});
// 03. Run WebView
mWebView.loadUrl(“http://google.com”);
}
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3. 2.3. AndroidManifest.xml (app/src/main/AndroidManifest.xml)
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package=“com.test.sample”>
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
<uses-permission android:name="android.permission.INTERNET" />
<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>
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4. 3. More
3.1. Download Listener (WebSettings)
3.2. KeyDown Event (Function)
public class MainActivity extends AppCompatActivity {
WebView mWebView = null;
ProgressBar progressBar = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
…
webSettings.setDisplayZoomControls(false);
webSettings.setLayoutAlgorithm(WebSettings.LayoutAlgorithm.SINGLE_COLUMN);
webSettings.setDefaultZoom(WebSettings.ZoomDensity.FAR);
mWebView.setWebChromeClient(new WebChromeClient(){
…
});
mWebView.setDownloadListener(new DownloadListener() {
@Override
public void onDownloadStart(String url, String userAgent,
String contentDisposition, String mimetype,
long contentLength) {
Intent i = new Intent(Intent.ACTION_VIEW);
i.setData(Uri.parse(url));
startActivity(i);
}
});
// 03. Run WebView
mWebView.loadUrl(“http://google.com”);
}
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) { … }
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if(keyCode == KeyEvent.KEYCODE_BACK && mWebView.canGoBack()){
if(mWebView != null){
mWebView.goBack();
return true;
}
}
return super.onKeyDown(keyCode, event);
}
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5. 4. Tips
4.1. 소스코드 정렬 단축키
4.1.1. Windows OS
: Ctrl+Alt+L
4.1.2. Linux OS
: Ctrl+Alt+L
4.1.3. Mac OS
: Option + Command + L
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