這是logcat的異常提示:java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.wangdan.sandpainting10/com.example.wangdan.sandpainting10.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ImageButton.setOnClickListener(android.view.View$OnClickListener)' on a null object reference而以下是我在mainActivity里寫的關(guān)于點(diǎn)擊監(jiān)聽事件的代碼:.setOnClickListener(View.OnClickListener(){
????onClick(View?arg0){
????????Intent?intent_settings=Intent(MainActivity.,settings.);
????????MainActivity..startActivity(intent_settings);
????}
});因?yàn)樾g(shù)語懂得不多,又是剛接觸安卓的新手,所以不大明白什么意思啊……謝謝啦??!
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XeonYu
TA貢獻(xiàn)12條經(jīng)驗(yàn) 獲得超9個(gè)贊
.setOnClickListener(new?OnClickListener()?{ @Override public?void?onClick(View?v)?{ Intent?intent=new?Intent(MainActivity.this,?settings.class); startActivity(intent); } });

星箜下
TA貢獻(xiàn)34條經(jīng)驗(yàn) 獲得超10個(gè)贊
引用沒有指向任何對(duì)象,Button有沒有findViewById? 寫在setOnClickListener前面,還有貼上來的這段代碼,Intent前沒new ?方法也沒返回值,MainActivity.this.startActivity()這樣寫的吧? ? ?難道寫這東西出了新方法?

waste_time
TA貢獻(xiàn)43條經(jīng)驗(yàn) 獲得超16個(gè)贊
.setOnClickListener(new View.OnClickListener(){
????onClick(View?arg0){
????????Intent?intent_settings=Intent(MainActivity.this,settings.class);
????????MainActivity.startActivity(intent_settings);
????}
});
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