Qt for HarmonyOS/qtohosextras doc/Start Ability For Result Example

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Start Ability For Result Example

Demonstrates starting another UIAbility and receiving its result asynchronously.

Three buttons start a target ability with QOhosAbilityContext::startAbilityForResult(): with a want only, with a want and start options built via QtOhosExtras::createStartOptions(), and with an intentionally empty want to exercise the error path. A dialog collects the target bundle and ability names. Every call returns a request identifier which is logged; results arrive through the startAbilityForResultResponseReceived() signal with the result code and an optional returned want, and failures through startAbilityForResultErrorResponseReceived().

Starting with a want only:

             [this, abilityContext]() {
                 auto want = tryGetWantFromTheUser();
                 if (want) {
                     auto requestId = abilityContext->startAbilityForResult(*want.get());
                     appendMessage(requestId, QStringLiteral("sent"));
                 }
             }));

Starting with a want and start options:

             [this, abilityContext]() {
                 auto want = tryGetWantFromTheUser();
                 if (want) {
                     auto startOptions = QtOhosExtras::createStartOptions();
                     startOptions->setWindowTop(0);
                     startOptions->setWindowLeft(0);

                     auto requestId = abilityContext->startAbilityForResult(
                         *want.get(), *startOptions.get());
                     appendMessage(requestId, QStringLiteral("sent"));
                 }
             }));

Handling the success and error responses:

     auto abilityContext = QtOhosExtras::QOhosAbilityContext::getDefaultInstance();
     QObject::connect(
         abilityContext.get(),
         &QtOhosExtras::QOhosAbilityContext::startAbilityForResultResponseReceived,
         this,
         [this](auto requestId, auto resultCode, auto want) {
             appendMessage(requestId, QStringLiteral("resultCode: %1").arg(resultCode));

             QMessageBox::information(
                 nullptr, "Success",
                 QStringLiteral("The result code from started ability: %1, has want: %2, request id: %3")
                     .arg(resultCode)
                     .arg(want != nullptr)
                     .arg(requestId.toHex().constData()));
         });
     QObject::connect(
         abilityContext.get(),
         &QtOhosExtras::QOhosAbilityContext::startAbilityForResultErrorResponseReceived,
         this,
         [this](auto requestId) {
             appendMessage(requestId, QStringLiteral("Error"));

             QMessageBox::warning(
                 nullptr, "Error",
                 QStringLiteral("An error occurred while starting ability for result. Request id: %1")
                     .arg(requestId.toHex().constData())
             );
         });

Note: Requests are asynchronous and several can be outstanding, so results must be correlated with the returned request identifier; there is no blocking variant of startAbilityForResult(). At minimum the bundle name and the ability name must be set on the want.

Files:

• abilitycontext/startabilityforresult/main.cpp
• abilitycontext/startabilityforresult/startabilityforresult.pro