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13 lines
2.8 KiB
Markdown
13 lines
2.8 KiB
Markdown
---
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id: backandroid
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title: backandroid
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---
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<a id="content"></a><h1>BackAndroid</h1><div><div><p>Detect hardware back button presses, and programmatically invoke the default back button
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functionality to exit the app if there are no listeners or if none of the listeners return true.</p><p>Example:</p><div class="prism language-javascript">BackAndroid<span class="token punctuation">.</span><span class="token function">addEventListener<span class="token punctuation">(</span></span><span class="token string">'hardwareBackPress'</span><span class="token punctuation">,</span> <span class="token keyword">function</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
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<span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token operator">!</span><span class="token keyword">this</span><span class="token punctuation">.</span><span class="token function">onMainScreen<span class="token punctuation">(</span></span><span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
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<span class="token keyword">this</span><span class="token punctuation">.</span><span class="token function">goBack<span class="token punctuation">(</span></span><span class="token punctuation">)</span><span class="token punctuation">;</span>
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<span class="token keyword">return</span> <span class="token boolean">true</span><span class="token punctuation">;</span>
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<span class="token punctuation">}</span>
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<span class="token keyword">return</span> <span class="token boolean">false</span><span class="token punctuation">;</span>
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<span class="token punctuation">}</span><span class="token punctuation">)</span><span class="token punctuation">;</span></div></div><span><h3><a class="anchor" name="methods"></a>Methods <a class="hash-link" href="#methods">#</a></h3><div class="props"><div class="prop"><h4 class="propTitle"><a class="anchor" name="exitapp"></a><span class="propType">static </span>exitApp<span class="propType">()</span> <a class="hash-link" href="#exitapp">#</a></h4></div><div class="prop"><h4 class="propTitle"><a class="anchor" name="addeventlistener"></a><span class="propType">static </span>addEventListener<span class="propType">(eventName: BackPressEventName, handler: Function)</span> <a class="hash-link" href="#addeventlistener">#</a></h4></div><div class="prop"><h4 class="propTitle"><a class="anchor" name="removeeventlistener"></a><span class="propType">static </span>removeEventListener<span class="propType">(eventName: BackPressEventName, handler: Function)</span> <a class="hash-link" href="#removeeventlistener">#</a></h4></div></div></span></div><div class="docs-prevnext"><a class="docs-next" href="cameraroll.html#content">Next →</a></div> |