Android 背压不起作用
这是我通过Imagebutton打开webview的主要活动 但我需要集成一个“backpress函数” MainActivity.javaAndroid 背压不起作用,android,Android,这是我通过Imagebutton打开webview的主要活动 但我需要集成一个“backpress函数” MainActivity.java package com.example.metehan.hbc; import android.app.Activity; import android.os.Bundle; import android.view.KeyEvent; import android.view.View; import android.webkit.WebView; im
package com.example.metehan.hbc;
import android.app.Activity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ImageButton;
public class MainActivity extends Activity {
private WebView webView;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final WebView wb = (WebView) findViewById(R.id.webviewactivity_webview);
wb.setVisibility(View.INVISIBLE);
final ImageButton ib = (ImageButton) findViewById(R.id.webviewactivity_imagebutton);
ib.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
wb.loadUrl("https://elearns02.fh-biberach.de/ilias3/login.php?target=&soap_pw=&ext_uid=&cookies=nocookies&client_id=HSBC&lang=de");
}
});
wb.setWebViewClient(new WebViewClient() {
public void onPageFinished(WebView view, String url) {
ib.setVisibility(View.INVISIBLE);
wb.setVisibility(View.VISIBLE);
}
});
}}
如果您从
startActivityForResult
打开新活动,则只需调用finish()
如果这不起作用,则在您的AndroidManifest.xml中将android:noHistory=“true”
设置为android:noHistory=“false”
如果上述操作不起作用,请在切换到新活动之前,尝试在主活动中调用finish()
对于您的情况,请尝试:
package com.example.metehan.hbc;
import android.app.Activity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ImageButton;
public class MainActivity extends Activity {
private WebView webView;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final WebView wb = (WebView) findViewById(R.id.webviewactivity_webview);
wb.setVisibility(View.INVISIBLE);
final ImageButton ib = (ImageButton) findViewById(R.id.webviewactivity_imagebutton);
ib.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
wb.loadUrl("https://elearns02.fh-biberach.de/ilias3/login.php?target=&soap_pw=&ext_uid=&cookies=nocookies&client_id=HSBC&lang=de");
}
});
wb.setWebViewClient(new WebViewClient() {
public void onPageFinished(WebView view, String url) {
ib.setVisibility(View.INVISIBLE);
wb.setVisibility(View.VISIBLE);
}
});
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (event.getAction() == KeyEvent.ACTION_DOWN) {
switch (keyCode) {
case KeyEvent.KEYCODE_BACK:
if (webView.canGoBack()) {
webView.goBack();
} else {
finish();
}
return true;
}
}
return super.onKeyDown(keyCode, event);
}
}}
此外,您可能希望将其标记为android和java。只是一个提示:你能用代码给我看一下吗?我真的很新^^^^但快速回答的thx我不在我的主计算机上,但这里有一个尝试。试着玩一下,看看有没有什么效果。编程中的挣扎是很自然的,每个人都会遇到。我试过代码,但@Override被称为“这里不允许注释”